Peder Rudolph Lykkeberg (1878–1944) was a Danish swimmer who competed at the 1900 Summer Olympics in Paris. He won the bronze medal in the underwater swimming competition. This event was held only in 1900. Lykkeberg had the longest time underwater (90.0 seconds compared to the winner's 68.4 seconds) and swam further than the other contestants (covering more than the winner's 60.00 metres), but Lykkeberg swam in a circle—and the distance for the scoring in the event was measured as a straight line from the starting point, resulting in his distance being credited as only 28.50 metres.